Added detection for the Pike language:

http://pike.ida.liu.se/

test/fixtures/rsif.pike

@@ -0,0 +1,22 @@
+#! /usr/bin/env pike
+// -*- pike -*- $Id$
+#pike __REAL_VERSION__
+
+inherit Tools.Standalone.process_files;
+string version = ("$Revision$"/" ")[1];
+string description = "Replaces strings in files.";
+string usage = #"[options] <from> <to> <files>
+
+rsif (\"replace string in file\") replaces all occurrences of the
+string <from> with the string <to> in listed files. The name of the
+files that were changed are written to stdout. Directories may be
+given instead of files, in which case all the files in that directory
+will be processed. Available options:
+" + default_flag_docs;
+
+int want_args = 2;
+
+string process( string input, string from, string to ) {
+  if( has_value( input, from ) )
+    return replace( input, from, to );
+}